Crude oil is pumped from wells and transferred to refineries for further processing. Many different molecules are present in the crude oil, and these molecules may be separated into various components that have different ranges of molecular weight and volatility. In one embodiment, the crude oil may be separated into light gases, naphtha, and heavy liquids. The naphtha may be used for a wide variety of purposes, including the production of gasoline for motor vehicles, and the production of several specialty chemicals.
Various aromatic compounds can be produced from the naphtha, such as benzene, toluene, xylene, and other aromatics. Aromatic products primarily contain aromatic compounds, but may include small quantities of other materials such as impurities or additives. The aromatic compounds can be isolated and separately sold for many purposes, including industrial aromatic products that may be used as reactants or solvents. The aromatic products are sold under various specifications that specify various properties of the product, such as purity, color, boiling point, distillation range, percent water, specific gravity, and a wide variety of other properties. Various grades or specifications are available, and products with more stringent specifications tend to sell at higher prices. Isolated and highly purified aromatic products are typically more valuable than gasoline, but sales typically depend on the aromatic products meeting specifications.
Olefins are unsaturated hydrocarbons that are not aromatics, but which do contain one or more double bonds. Olefins are a component of naphtha, and they are undesirable impurities in some aromatic products. One method of removing olefins involves reacting the olefins to produce other products that are more easily removed from the aromatics, but some of these reaction products create colored bodies. A small concentration of colored bodies imparts a noticeable color to an aromatic product, and the color may render the aromatic product out of specification. Separation methods can be used, but separation methods require energy, equipment, and processing time, all of which increase the production cost of the final aromatic product.
Accordingly, it is desirable to provide simple, quick, and inexpensive systems and methods for providing and purifying aromatic products. Furthermore, other desirable features and characteristics of the present application will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.